Spring winding machine



Jan. 28, 1969 "R. LUDWIG ET AL 3,423,980

SPRING WINDING MACHINE 6 E E0 v 7 v0 L m w 9 WV m a m R e a N mm wk 9% QR Q N N 6 1 mm 3 We Jan. 28, 1969 R. L. LUDWIG ETAL 3,423,980

SPRING WINDING MACHINE Filed Aug. 15, 1966 Sheet 2 of2 I N VENTORS 408b??? A. LUDW/G 6. A 0) @054 ING United States Patent 6 Claims Int. Cl.1521f 3/04, 3/10 ABSTRACT OF THE DISCLOSURE A spring winder comprising arotating mandrel and a free moving carriage, with jaw means on thecarriage to support the mandrel and to impart an adjustable pitch to thespring. The spring, as it is being formed, causes the carriage to moveaxially of the mandrel while maintaining pitch.

This invention pertains to machines for winding springs, particularlytension and compression springs.

As used herein, sizes refers to springs with diiferences in any or allof their parameters; namely, stock size, inside diameter, length, pitch,and the like.

The invention is directed to the problem present in many machine shops,factories, and the like, of obtaining small quantities of many differentsizes of springs. The obtaining of a very small number; for example, oneor two, of a particular size spring can often involve a great deal oftime and money in that a highly skilled machinist, and sometimes twosuch workers, or other skilled workmen, must be taken from their regularwork and put to producing these special springs.

Another problem solved by the present invention is the provision of ahighly simplified machine of the character described. Prior machineshave been characterized by the inclusion of a positive feed, such as apower driven feed screw, or equivalent element, to move the carriagealong the bed. An advantage of the present invention is the eliminationof such feed screws or equivalent elements, thus simplifying manufactureand use of the machine, and effecting substantial economies in itsmanufacture and maintenance. The function of the feed screw, impartingpitch to the spring, is carried out in the present invention by thestock guide in cooperation with the stock itself and the coils of thespring being formed, as Well as a portion of the carrier, and is donesubstantially automatically. The invention also permits changing thepitch while the machine is running to produce a spring having a compoundpitch.

The invention accordingly comprises a machine adaptable for use by theaverage Worker as opposed to the highly skilled worker to produce manydifferent sizes of springs economically, quickly, and easily, andsubstantially automatically after the machine is set up.

A machine embodying the invention comprises a flat, longitudinal bedhaving a power source mounted at one end. from which extends alongitudinal mandrel. A carriage is freely slidable on the bed and feedsthe spring stock onto the mandrel, with means to impart anypredetermined pitch to the spring as it is being Wound, which means areadapted to push the carriage longitudinally of the mandrel as the stockis formed into a spring.

In the accompanying drawing forming a part of this disclosure:

FIG. 1 is an overall perspective view of a machine embodying theinvention;

FIG. 2 is a cross-sectional view taken on line 2-2 of FIG. 1 showing thepitch adjustment mechanism;

FIG. 3 is a cross-sectional view taken on line 3-3 of FIG. 1; and

FIG. 4 is a view of the mandrel and stock guide with the stock guidecover removed showing the path of the stock therethrough.

Referring now in detail to the drawing, 10 designates a machineembodying the invention. Machine 10 comprises a bed 12 which consists ofa base member 14 which is in the form of a C channel positioned with itslegs up. Mounted on the ends of the legs of C channel 14 and fixedthereto by any suitable means, such as by welding,

is a top bed plate 16. Bed plate 16 comprises a flat, top,

finished surface 18 and a pair of finished, longitudinal edge surfaces20. Finished surfaces 18 and 20 permit easy, unrestricted motion of thecarriage thereon for a reason which will appear more clearlyhereinafter.

Fixedly mounted, as by welding or other suitable means, at one end ofbed plate 16 are bracket means 22 on which is mounted a mandrel driveunit 24. Drive unit 24 may comprise any suitable power source, such asan air motor or an electric gearmotor, the only requisites being that,the output turn at a relatively slow speed, it have means to adjust thespeed, and it have means to reverse direction. In the preferredembodiment of the invention, drive unit 24 comprises an air motor withsuitable valving to adjust the speed and reverse direction, whichvalving is conventional and not shown.

Mounted on the output end of drive unit 24 is an adjustable chuck 26which permits the use of various different mandrels 28. The outer end ofmandrel 28 is slotted as 29 to receive the end of the spring makingstock S.

Slidably mounted on bed 12 is a carriage assembly 30. Carriage 30comprises a pair of opposed L shaped end plates 32, each having a bottomflange 34 which extends below the overhanging edge of plate 16. Each endplate 32 further comprises an upwardly extending flange 36, whichextends above top surface 18 of bed plate 16. Each flange 36 carries afirst pair of anti-friction rollers 38 disposed in horizontal planes andriding against finished, edge surfaces 20 of bed plate 16. Each flange36 also carries a second pair of anti-friction rollers 40 disposed invertical planes and riding against top finished surface 18 of bed plate16.

Thus, rollers 38 and 40 are the only connection be tween the carriage 30and the bed plate 16, and therefore, carriage 30 is free to move alongthe plate. The carriage can be simply rolled ofi the free end of the bedplate, if desired, for adustmeuts, lubrication, and the like andremovable stop means, not shown, may be provided to prevent the carriagefrom rolling off while the machine is in use.

Interconnecting flanges 36 between the rollers 38 and 40 is a topslotted carriage plate 42. Adjustably mounted on carriage plate 42 are apair of jaws 44 and 50. law 44, in a horizontal plane, is centrallynotched out to form a pair of legs 44a, which renders the jaw generallyU shaped. In a vertical plane, legs 44a are notched out as at 48. Notch48 forms a square corner, the edges of which are disposed at a 45 angleto the horizontal, and has its axis at the vertical center line of jaw44.

J aw 44 is movably mounted on the carrier by means of a bolt 46 passingthrough a suitable opening in jaw 44 and extending down below plate 42into a traveling block 53. Similarly, jaw 50 is movably mounted on thecarriage by means of a bolt 52 passing through a suitable opening in jaw50 and extending down below plate 42 into a similar traveling block 54.Perpendicular to the axes of bolts 46 and 52 is an adjusting screw 56which passes through suitable oppositely threaded openings in thetraveling block, a suitable opening 36a in flange 36 of one end plate32, and terminates in a crank handle 58. Screw 56 comprises a firstthreaded portion 53a and a second oppositely threaded portion 54a,cooperating with the blocks 53 and 54. Thus, by turning crank 58, the

blocks 53 and 54 will move together or apart from one centerline. Theother end of screw 56 rides in a blind opening 57 in the opposite endplate 36 for support.

Jaw 50 is of a thickness in the direction of the axis or mandrel 28 tofit snugly between the legs 44a of jaw 44, and is notched out as at 60with a right angle notch similar to and symmetrically disposed to notch48 in jaw 44. Thus, the space between the notches 48 and 60 is a squarein a vertical plane, and the size of this square can be adjusted bymeans of crank 58 to move the jaws together or apart. Mandrel 28 looselyrides in this square, and the center line of the square is made tocoincide with the center line of the mandrel when the jaws and theirtraveling blocks are assembled onto screw 56.

For convenience, the longitudinal direction along the bed from thecarrier 30 towards drive unit 24 shall be considered rearward, and theopposite direction forward.

Jaw 50 also carries means 62 to adjust the pitch of the spring as it isbeing formed, see FIG. 2. Pitch adjustment means 62 comprises a member64 having a central, plain, cylindrical shank portion 66 passing througha suitable opening in jaw 50. Extending rearwardly from shank portion66, member 64 comprises a threaded portion 68. Threadedly mounted onthreaded portion 68 is a hand adjustment nut 70. law 50 comprises aplurality of rearwardly extending lugs 74 which overlap a front flange72 on nut 70 to keep nut 70 closely adjacent the rear surface of jaw 50.Thus, turning nut 70 will move member 64 axially with respect of jaw 50.The front end of member 64 comprises a threaded stud portion 76, onwhich is threadedly mounted a stock guide tightening nut 78.

Mounted on member 64 is a stock guide and tensioning assembly 80.Assembly 80 comprises a rear plate 82, which is formed integral withmember 64 at the forward end of cylindrical portion 66. Rear plate 82could also be formed as a separate member, as will be evident to oneskilled in this art. Rear plate 82 comprises a forwardly extending pin84 positioned furthest outwardly from the axis of member 64. Exetendingboth forwardly and rearwardly from rear plate 82 radially inwardly ofpin 84 is a second stock guide pin 86. The rearwardly extending portionof pin 86 fits into any one of a plurality of holes 88 formed in jaw 50.The positioning of the rear portion of pin 86 in any one of the holes 88determines the angular position of assembly 80 with respect to the axisof mandrel 28. This angular position is important when using heaviersizes of stock, in that such heavier stock may kink, and when using suchheavier sizes, the angular position is suitably adjusted to achieve asubstantially straight delivery of stock to the mandrel, depending, ofcourse, upon the direction of rotation of the mandrel. As shown in FIG.4, the feed stock S is fed between the two pins 84 and 86 so that it isfirmly held and fed regardless of the direction of rotation of themandrel. With exceptionally heavy stock, it may be necessary to by-passthese pins, but such large stock is stiff enough so that additionalsupport would not be needed.

Assembly 80 further comprises a front plate 90, which is formed withthree suitable openings which slidably receive pins 84 and 86 and theshank portion of member 64 between threaded portion 76 and cylindricalportion 66, respectively. Assembly 80 is removably held together by thenut 78, which also serves to tighten the plates 82 and 90 onto feedstock S. Tension is necessary on the feed stock to obtain tight, regularcoils.

Operation The operation is most readily explained by way of a specificexample.

It was desired to make a coil tension spring having an inside diameterof A inch, a length of 2% inches, from inch diameter carbon spring steelwire. A mandrel was selected having a diameter of inch. The mandreldiameter is somewhat smaller than the inside diameter of the springbecause it is necessary to allow for the expansion of the spring afterit is formed and the tension released.

The releasing of this tension is another problem solved by the presentinvention which is present in prior devices. This problem is thesubstantial danger of physical harm to the operator when releasing woundsprings from mandrels that have not had the tension stored in themduring their formation relieved before removal. The problem is solved inthe present invention by reversing rotation of the mandrel until thetension is released, in effect unwinding the tension, and then cuttingthe stock to remove the finished spring. Normal finishing operations,such as flattening the ends, or the like, may be performed in theconventional manner, if desired.

The drive unit 24 was adjusted for a rotational speed of about 120 rpm.Nut 70 was turned to move member 64 carrying nut 78 and assembly 80forwardly to make room in which to work. The nut 78 and front plate wereremoved. Stock S was run between pins 84 and 86 and into the mandrelslot 29. The plate 90 and nut 78 were put back into place and nut 78tightened to put drag or tension on stock S. This drag or tension on thefeed stock is required to insure tight wrapping of the wire on themandrel and to assure uniform coils. It will be noted that once plate 90and nut 78 are adjusted, they may be moved as a unit by rotation of nut70. Before feeding the wire onto the mandrel, crank 58 was turned tobring jaws 44 and 50 snugly up against mandrel 28. This enclosed mandrel28 in the square defined by notches 48 and 60 in the jaws. The pressureapplied via crank 58 is such that the mandrel is just supported, and notbound or restricted against rotation.

Nut 70 was then turned in the opposite direction to move the center lineof the stock S between plates 90 and 82 rearwardly of the front face ofjaw 44. It will be noted that the relative position, in a horizontalplane, between the center line of the stock S between the jaws 82 and 90and the front vertical face of the jaw 44 determines the pitch of thecompleted spring, which in this case Was 7 coils per inch. To achievethis pitch, under these conditions, the spacing between the center lineof the feed stock between the jaws and the front face of jaw 44 was toosmall to measure. The operator turns nut 70 slowly until the properpitch is imparted. Only very slight adjustment is required.

The embodiment of the invention used to fabricate the spring of theabove example is capable of winding springs having inside diametersvarying from inch to more than 5 inches, using stock varying in diameterfrom .0126 inch to .750 inch.

It will be understood that during preparation the carriage 30 is at thefront end of mandrel 28. After the machine is setup, the drive unit 24is turned on and the spring proceeds to wind itself, with the pitchbeing automatically imparted to the spring by pressure of the feed stockpassing from the jaw to the mandrel against the front face of jaw 44.

Referring to FIG. 2, it will be seen that moving assembly 80 to theright will result in springs having a larger pitch and moving it to theleft will result in springs having a smaller pitch, with the extreme ofthis leftward motion being a tension or pull spring having no spacesbetween the coils.

Another feature is that pitch adjustment nut 70 can be turned while thespring is being formed. This permits production of springs havingvariable pitch, or production of a number of short springs during onerun of the machine with portions of large open pitch between portions ofclose pitch to facilitate cutting the overall spring apart to thuseffect economies in the use of material. Since the pitch can be adjustedwhile the machine is running, it is possible to make a spring with avery precise pitch when needed, as well as with a compound pitch.

Other variations of springs which it is possible to make include conicalsprings or springs having tapered ends. This is readily accomplishedwith the use of the embodiment of the invention as described above,except that a conical or a tapered ended, or otherwise specially formedmandrel, is substituted for mandrel 28.

It will be seen that the present invention provides simple to operateand uncomplicated means by which many diiferent sizes of springs can bemade and in which the pitch is imparted to the spring automatically bythe coils of the formed spring itself, which coils progressively movecarriage 30 rearwardly towards power source 24 as they are formed.Reversing direction of the mandrel permits release of the stored energywithin the spring to eliminate a serious safety hazard present in priordevices.

When using relatively large diameter or special mandrels it is, ofcourse, possible to substitute a larger capacity chuck for chuck 26shown.

While the invention has been described in some detail above, it is to beunderstood that the protection granted is to be limited only within thespirit of the invention and the scope of the following claims.

Therefore we claim:

1. In combination, a base member, drive means on said base member, amandrel, means to mount said mandrel on said drive means in spacedrelation to said base member for rotation of said mandrel about itsaxis, carriage means, means to mount said carriage means on said basemember for free motion of said carriage means on said base memberaxially of said mandrel, said carriage means comprising means to feedspring making stock onto said mandrel, said carriage means furthercomprising means cooperable with said spring making stock and saidfeeding means to move said carriage means axially of said mandrel onsaid base member to impart a predetermined pitch to a spring beingformed on said mandrel, said carriage means comprising a pair of jaws,means on said carriage means to adjust the relative positions of saidjaws to each other and to the axis of said mandrel, one of said jawscomprising a pair of spaced legs, the other of said jaws comprising aportion receivable between said legs, said feeding means comprising apair of plates on said other jaw, means to adjust the spacing betweensaid plates to accommodate various sizes of spring making stocktherebetween, and said cooperable means comprising means to adjust theposition of said plates with said stock therebetween with respect to aportion of said one of said jaws.

2. The combination of claim 1, said feeding means further comprisingmeans to apply tension to the spring making stock feeding between saidplates to said mandrel.

3. The combination of claim 1, one of said plates comprising a pair ofpins extending outwardly therefrom, the other of said plates beingformed with a pair of openings adapted to slidingly receive said pins,where- :by said stock feeding between said plates to said mandrel maypass between said pins, whereby said stock is retained to feed betweensaid plates in both directions of rotation of said mandrel.

4. In combination, a base member, drive means on said base member, amandrel, means to mount said mandrel on said drive means in spacedrelation to said base member for rotation of said mandrel about itsaxis, carriage means, means to mount said carriage means on said basemember for free motion of said carriage means on said base memberaxially of said mandrel, said carriage means comprising means to feedspring making stock onto said mandrel, said carriage means furthercomprising means cooperable with said spring making stock and saidfeeding means to move said carriage means axially of said mandrel onsaid base member to impart a predetermined pitch to a spring beingformed on said mandrel, said feeding means comprising a pair of plates,means to adjust the spacing between said plates to accommodate varioussizes of spring making stock therebetween, and said cooperable meanscomprising means to adjust the position of said plates with said stocktherebetween with respect to a portion of said one of said jaws.

5. The combination of claim 4, said feeding means further comprisingmeans to apply tension to the spring making stock feeding between saidplates to said mandrel.

6. The combination of claim 4, said plates comprising a pair of pinsextending therebetween, whereby the spring making stock feeding betweensaid plates is restrained to pass between said plates.

References Cited UNITED STATES PATENTS 963,512 7/1910 Butterworth 72-1432,054,196 9/1936 Gogan 72144 X 2,325,462 7/1943 Arthur 72144 2,649,1308/1953 Border 72-144 2,811,193 10/1957 Iversen 72143 FOREIGN PATENTS585,792 10/1933 Germany.

4,400 8/1893 Sweden.

MILTON S. MEHR, Primary Examiner.

U.S. Cl. X.R. 72138

